1. Field of the Invention
The present invention relates generally to virology and disease control. Specifically, the present invention relates to mutated arthropod vectored viruses and their uses as vaccines.
2. Description of the Related Art
Arthropod vectored viruses (Arboviruses) are viral agents which are transmitted in nature by blood sucking insects. Arboviruses include members of the alpha-, flavi- and bunyaviridae. Over 600 of these viruses are presently known and emerging members of these families are being described annually. Collectively, the arthropod vectored viruses are second only to malaria as a source of insect-transmitted disease and death in man and animals throughout the world (Berge A. O. 1975). Among these viral agents are Eastern, Western, and Venezuelan Equine Encephalitis Viruses, Dengue Fever, Japanese Encephalititis, San Angelo Fever, West Nile Fever and Yellow Fever. Furthermore, diseases caused by these agents are in resurgence in North America (NIAID Report of the Task Force on Microbiology and Infectious Diseases 1992, NIH Publication No. 92-3320) as a result of the introduction of the mosquito vector Aedes albopictus (Sprenger, and Wuithiranyagool 1985).
By their very nature, Arboviruses must be able to replicate in the tissues of both the invertebrate insect and the mammalian host (Brown, D. T., and L. Condreay, 1986, Bowers et al. 1995). Differences in the genetic and biochemical environment of these two host cell systems provide a basis for the production of host range mutant viruses which can replicate in one host but not the other.
Currently, Dengue Fever and Eastern Equine Encephalitis and other insect borne viruses are in resurgence in the United States. The U.S. Army and other government agencies have been trying to make vaccines against these viruses since the 1960s with little success. Thus, the prior art is deficient in a vaccine against most arthropod vectored viruses and other membrane-coated viruses. The present invention fulfills this long-standing need and desire in the art.